Problems building GNU Greg testing framework

[romel]

Hello,

I'm trying to build GNU Greg 1.4 in order to build Guile DBI but when I
run ./configure something goes wrong.

$ ./configure --prefix $HOME/opt/
loading cache ./config.cache
checking host system type... Invalid configuration
`x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized

checking target system type... Invalid configuration
`x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized

checking build system type... Invalid configuration
`x86_64-unknown-linux-gnu': machine `x86_64-unknown' not recognized

checking for gcc... (cached) gcc
checking whether the C compiler (gcc  -I/home/romel/opt/include
-I/home/romel/opt/include/guile/2.0 -L/home/romel/opt/lib) works... yes
checking whether the C compiler (gcc  -I/home/romel/opt/include
-I/home/romel/opt/include/guile/2.0 -L/home/romel/opt/lib) is a
cross-compiler... no
checking whether we are using GNU C... (cached) yes
checking whether gcc accepts -g... (cached) yes
checking how to run the C preprocessor... (cached) gcc -E
checking for ranlib... (cached) ranlib
checking for ld used by GCC... (cached) /usr/bin/ld
checking if the linker (/usr/bin/ld) is GNU ld... (cached) yes
checking for BSD-compatible nm... (cached) /usr/bin/nm -B
checking command to parse /usr/bin/nm -B output... (cached) yes
checking for _ prefix in compiled symbols... (cached) no
checking whether ln -s works... (cached) yes
ltconfig: you must specify a host type if you use `--no-verify'
Try `ltconfig --help' for more information.
configure: error: libtool configure failed

I'm using guile 1.9.14 builded in ~/opt and I have set the following
environment variables:

export LDFLAGS="-L$HOME/opt/lib"
export CPPFLAGS="-I$HOME/opt/include -I$HOME/opt/include/guile/2.0"
export PKG_CONFIG_PATH="$HOME/opt/lib/pkgconfig"
export LD_LIBRARY_PATH="$HOME/opt/lib/"
export PATH="$HOME/opt/bin:$PATH"

I'm running Trisquel 4 taranis in an AMD 64 machine.

Anybody can bring some light to this issue?

Thanks in advance.

Regards,

Romel Sandoval